Maximum-demand meter.



Patented Dec; II, 1900.

E. OXLEY. MAXIMUM DEMAND METER. (No Model.) (Application filed July 31,1899-] 2% El :30 59 16 i 5 4 T5 Fig.2. 5:

Inventor. Edstac'e Oxtey \A/itnesses. I

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EUSTAGE OXLEY, OF LYNN, MASSACHUSETTS, ASSIGNOR TO THE GENERAL ELECTRICCOMPANY, OF NEW YORK.

MAXIMUM-DEMAND METER.

SPECIFICATION forming part of Letters Patent No. 663,461, dated December11, 19

Application filed July 31, 1899.

To all whom it may concern: 4

Be it known that I, EUSTAOE OXLEY, a subject of the Queen of GreatBritain, residing at Lynn, county of Essex, State of Massachu- 5 setts,have invented certain new and useful Improvements in Maximum-DemandMeters, (Case No. 1,094,) of which the following is a specification.

This invention relates to a device for indicating the maximum demand ofa consumption-circuit containing translating devices that is to say, themaximum number of such translating devices in use at one time or themaximum strength of current used at any time in the consumption-circuit.

In carrying out the invention I employ a fluid column the level of whichis capable of being electrically disturbed under the influence of acurrent. I so arrange the connections that this disturbance isproportional to the strength of current influencing the column andprovide means for trapping the fluid when raised under the influence ofthe current above a predetermined level, so as to leave a record of themaximum disturbance which has occurred during a given period of serviceand for retarding its change of level to afford a slow movement and adda time factor to the meter indication.

More specifically considered, my invention relates to anelectrically-controlled device in which a conducting fluid or part ofthe same is within the influence of a magnetic field and provided withterminal electrodes in contact with the liquid within the field offorce. On one side the liquid is in communication with a reservoir andon the other side with a tube. Under these conditions when the currentis passed through the electrodes the mutual repulsive action of theelectrostatic and magnetic fields created by the magnet and current,respectively, acts as a pump, causing the level of the liquid to bedisturbed in the tube and raised in proportion to the strength of thecurrent passing between the electrodes. The pumping action will continueuntil the repelling force determined by the electrostatic andelectromagnetic fields is balanced by the hydrostatic pressure due tothe difference in level between the liquid in the reservoir and that inthe tube. I provide also Serial No. 725,602. (No model.)

means for leaving an indication of the maximum disturbance of level,which may be a trap or some other convenient device by which the returnof the liquid in the tube when raised above a predetermined level isprevented. This may assume various forms; but that which I prefer is avalve which permits the rise of the liquid in the tube, but is seatedwhen the current ceases or declines in strength, thus retaining ortrapping the liquid within the tube. If at any later period a greaterstrength of current be employed in the circuitthat is to say, if alarger current be used in the consumption-circuitthe valve will be freeto permit more liquid to be pumped into the tube and the level to bestill further raised, and after the period of increased-current demandhas elapsed the valve will again seat. It will be obvious, however, thatmany other methods might be devised and will occur to those skilled inthe art for trapping the liquid displaced, so as to indicate the maximumquantity of liquid moved or maximum level to which it is raised.

- I prefer also to add to the device a time-indicating factor by whichthe level of the liquid may be disturbed only in a slow manner, therebyinsuring that if the maximum demand occur for only a very brief intervalthe meter will not register.

My invention therefore comprises a meter of the kind referred to inwhich means are pro vided for transferring the fluid from one level toanother proportionately to the strength of currentin theconsumption-circuit and means for indicating the maximum difierence ofsuch levels.

It comprises also other and more specific features which willhereinafter be more fully 0 noted and will be specifically pointed outin the claims.

In the drawings illustrating my invention, Figure 1 is a sectional viewof a device embodying my improvements. Fig. 2 is an ele- 5 vation on aplane at right angles to that indicated in Fig. 1.

1 represents a magnet, which may be an electromagnet or a permanentmagnet, the field of force of which is traversed by a conduct- IOO ingfluid. \Vithin the field of force or in such relation thereto as topermit the transmission of an electric current across the same are twoconducting-electrodes 2 2, which form terminals,to which may beconnected the consumption-circuit. The electric and the magnetic fieldsshould be symmetrically related with relation to their centers.Otherwise the desired pu mping action will not occur. The electrodes aresealed fluid-tight where they pass through the walls inclosing thefluid. On one side of the magnetic field is an enlarged reservoir tocontain the body of fluid, as indicated at 3,and on the other side is avertical tube 4:, graduated to indicate the relative displacement of theliquid under different strengths of current. Within the tube is a valve5, which may be packed on the outside, or its seat may be packed withsome soft material to form a fluid-tight joint when the valve is seatedunder the pressure of the displaced fluid,assisted by the tension of alight coil-spring 6. A stem connected to the valve passes through asuitable part of the containing vessel and is provided with a knob orhandle 7, which permits the valve to be unseated and controls the returnflow of the liquid when the meter is reset. I providealso in the tube acock 8, provided with a narrow perforation, which may be turned todiiferent angles, so as to permit a larger orsmaller channel of communication between the tube and the reservoir in a manner similar to agas-key, which will be readily understood.

As thus organized, when the device is put in series relation to theconsumption devices in an electric circuit, stream lines of currenttraverse the liquid between the electrodes, and the chains ofliquid-electrified molecules are repelled by the magnetic field inaccordance with a well-known principle of physics and in a definitedirection, depending on the direction of current. The strength of therepulsion is determined coordinately by the strength of the magneticfield and the strength of the current flowing across the liquid. Thedevice will thus act after the fashion of a pump forcing the liquid fromthe reservoir into the tube until the hydrostatic pressure is sufficientto counterbalance the molecular repulsion by the magnetic field offorce. The valve should be so organized that it will not offer materialresistance to flow in one direction and will easily seat against atendency to counterflow. Thus under the influence of the current liquidis pumped up into the tube 4 and when the translating devices are cutoff cannot flow back. This action is slowly effected by reason of thesmall opening governed by the cock 8. Consequently if the period ofexcessive current admission be short the liquid will not have sufficienttime to accumulate to raise it above a predetermined zero level. Ifcontinued forsome time, however, it passes this level and leaves arecord that more than the average demand has been made upon thetranslating devices. If at a subsequent period before the resetting ofthe meter a greater demand should be made upon the current, the levelwill be proportionately raised and the maximum amperage always indicatedby the graduation corresponding to the level at which the liquid stands.In resetting the meter itis only necessary to push up the knob 7 andturn on the key to its full open position. when the two liquid columnson the two sides will assume a normal hydrostatic balance and theapparatus will be in condition for further use.

In order to permit a convenient and sensitive operation of thedevice,leak-holes for air should be provided in the tube and in the reservoir,as indicated, to permit a free movement of the conducting liquid underthe influence of the current. I prefer to employ as a conducting liquidmercury, sinceit will carry a current without the liberation of gases.Any conducting liquid, however, or fluid would be within the scope of myinvention.

What I claim as new, and desire to secure by Letters Patent of theUnited States, is-

1. A maximum-demand meter comprising a liquid, means for disturbing thehydrostatic balance proportionally to the strength of current in aconsumption-circuit controlling said fluid, and an indicating device tomake a continuing indication of the maximum difference of level.

2. A maximunrdemand meter comprising a liquid, means for moving the sameproportionately to the energy controlling it, an indicator for showingthe extent of its movement, and means for preventing an indication ofenergy fluctuation of short duration.

3. A maximum-demand meter, comprising a liquid, means for transferringthe same from one level to another proportionally to the strength ofcurrent in a consumption-circuit controlling said transfer, and a trapfor the transferred liquid.

at. A maximum-demand meter comprising a liquid,electrically-controlleddevices to disturb the hydrostatic balance ofsaid liquid proportionally to the strength of current in aconsumption-circuit governed by the meter, and a valve to preventbackflow of the liquid when raised above a predetermined level.

5. A maximum-demand meter comprising a conducting liquid communicatingwith a reservoir on one side and a tube on the other and traversing amagnetic field at a suitable point, electrodes within the field forinclusion in the consumption-circuit, whereby the liquid is displacedwhen conducting current, and a valve to prevent backflow of the liquidwhen raised above a predetermined height.

6. A maximum-demand meter comprising a conducting liquid communicatingwith a reservoir on one side and a tube on the other and traversing amagnetic field at a suitable point, electrodes within the field forcommunicating with a consumption-circuit, and a valve to preventbackflow of the liquid when raised above a predetermined height, saidreservoir on one side and a tube on the other and traversing a magneticfield at a suitable point, electrodes within the field for connectionwith a consumption-circuit, a valve to prevent backfiow of the liquidwhen raised above a predetermined height, and an adjustable openingcontrolling the admission of fluid to the tube to vary the time elementof the meter indication.

In Witness whereof I have hereunto set my hand this 27th day of July,1899.

EUSTAOE OXLEY.

Witnesses:

DUGALD HoKILLoP, J OHN MOMANUS.

